An instrument for reproducibly and accurately measuring the liquid absorbency and related properties of a material is useful in the arts relating to absorbent products. Such absorbent products include surgical dressings, disposable diapers, sanitary products, and the like. The present invention is addressed to just such an apparatus which not only provides accurate and reproducible results, but which is also quite versatile in that it can determine liquid absorbency and related properties in a number of different modes simulating different use conditions. The instrument can determine various properties, such as the total quantity of liquid retained by a product under loaded or no-load conditions, the rate at which liquid is taken up, and the rate at which liquid is expressed under load.